1. Field of the Invention
The present invention relates to an actuator drive control device comprising a controller and an actuator, the controller supplying a target electric current to the actuator to periodically drive the actuator in an expanding and contracting manner with a target vibration waveform.
2. Description of the Related Art
Japanese Patent Application Laid-open No. 2002-139095 discloses an actuator drive control device, in which the driving cycle of an actuator is divided into a large number of very small time regions, and the duty ratios of the very small time regions are individually controlled, in order to drive a movable member of an active vibration isolation support system with a vibration waveform of a sine wave shape, so that a target electric current of a sine wave shape is supplied to the actuator.
In the case where an actuator using a solenoid is periodically driven in an expanding and contracting manner, an electric current waveform of a sine wave shape input to the actuator and a vibration waveform of the movable member of the actuator establish a nonlinear relationship therebetween, and a primary vibration waveform of a sine wave shape for the movable member is overlapped by higher-order vibration waveforms such as a secondary vibration waveform having a twofold frequency and a tertiary vibration waveform having a threefold frequency, so that it is disadvantageously difficult to vibrate the movable member of the actuator in an accurate sine wave shape.